Procedures for the operation of lighting systems and corresponding lighting systems for producing a first and a second light function are well-known. They are used e.g. in motor vehicles in order to provide a low-beam light as a first light function and a high-beam light as second light function by means of head lights. In these well-known procedures and lighting systems, there is a provision for switching between low-beam and high-beam light. It is also well-known, that the high-beam light presents a selective high-beam light, in particular a regulated high-beam light. This refers to a use of the high-beam light, even if approaching traffic is appearing in front of the motor vehicle. With a selective or regulated high-beam light, a selective and thus a particular prevention of the glare of the approaching traffic can be accomplished. In the well-known lighting systems it is thus possible, that the illumination is performed around the approaching traffic in the manner of a high-beam light, but without producing a glare to the approaching traffic. This leads to an improved illumination in front of the motor vehicle.
Yet, the disadvantage of such known procedures for lighting systems and of such-like lighting systems is, that there is a danger of producing a glare to the approaching traffic when the control of the high-beam light fails, in particular when the selective high-beam light fails. If e.g. a mechanically operated aperture is used to avoid producing a glace to the approaching traffic, it can happen, that this mechanism is stuck or that a precise positioning of the aperture is not possible. This results in the danger of producing a glare to the approaching traffic. This is to be avoided in order to reduce the risk of producing a glare to the approaching traffic on the roads. Thus, it is necessary to deactivate the entire light module when such an error occurs in a common lighting system and in a well-known procedure for controlling such lighting systems, wherein both light functions, which includes the high-beam light as well as the low-beam light are turned off. The corresponding headlight is thus turned off, so that the low-beam light, which actually would not add to the glare to the approaching traffic, is weakened as well when one of the two headlights and the corresponding light module is deactivated. So, in the case of an error of a selective high-beam light, the illumination is reduced more than what would actually be necessary,